I just purchased brand new 70-200 f2.8 is ii a few days ago and after half a day of shooting with 5d3 i feel something loose from camera or lens. I am not sure where the movement its coming from but it cannot be heard, i can only feel it (something loose) when tilting the camera or with any movement. So i did some experiments and came to conclusion that the slight movement came from between the lens mount and camera mount. when i firmly press in the lens towards the camera, no play at all.

when the lens is mounted onto camera i can hear the lock engaged and it seems firm but if you were to use a little force to move left or right you can feel little play, there is no up-down movement just left and right. now i am a little concern because i've never own a heavy, nor have any telephoto lens prior to this one so i am not sure if this is normal for telephoto lens or the lens itself needs to be exchange? and my 17-40 and 135 f2 seems perfectly fine when mounted on my 5d mark iii. no movement at all.

does anybody here encounter the same problems with their 70-200 f2.8 is ii.

The lens has a slightly oval hole that the pin on the camera side drops into. Based on tolerance build up and wear, they eventually all become loose.Its not a big deal, but if there is a lot of play, it can be annoying. My 600mmL had a lot of polay, so I pulled the mount off the lens, hit it a good lick with a punch to close up the hole and it was fine thereafter.

When I first got my 70-200 2.8 ii I noticed the same thing...and it worried me. I posted the problem here and found that it is common...as long as iq is good, don't worry.

I was so worried about it at first that I drove to two different camera stores and tested 4 different versions of the 70-200 from canon and Nikon on the store's 5d3 and d800....all had some wiggle/play.

My 70-200 and 300 both wiggle on my 1dx and 5d3.....wiggle is normal.

I would also add that the 70-200 2.8 ii might be the best lens ever made by canon or Nikon...it's that good...enjoy.

When I pop my 400L on a sturdy tripod....the only movement is between the camera and the lens mount. If I use a Teleconverter, this increases a little. It's just a bit of lens mount rotational slackness.